Computers and computing systems have impacted nearly every aspect of modern living. For example, computers are generally involved in work, recreation, healthcare, transportation, navigation, entertainment, household management, etc.
Modern navigation systems and object detection systems heavily rely on computing systems to provide real-time, accurate depictions of the physical world and to identify objects within that world. For instance, using various detection equipment (e.g., a Global Positioning System (GPS), a radar array, etc.), these systems can produce a real-time map of a particular environment; this map can include the various geographic features and structures that are present within that environment. The information provided from this real-time map can be critical in some situations. By way of example, commercial airliners that are flying through the air need to safely avoid other objects. By using integrated navigation systems and object detection systems, the airliners can safely travel through the air without obstruction. Here, it is worthwhile to note that some object detection systems include the use of a radio frequency (“RF”) detection system. These RF detection systems are able to actively listen and detect RF transmissions. Using these RF detection systems, the object detection systems are able to provide more thorough and robust information when detecting and tracking objects within a particular environment.
Many different types of transport vehicles and/or base stations use navigation systems and object detection systems (including RF detection systems). As used herein, the term “vehicle” refers to any type of aircraft, sea craft, or land-based movable carrier. In light of this definition, the term “vehicle” should be construed broadly, and its interpretation should not be limited to any specific form. Continuing from above, many modern-day automobiles often have either a built-in or removable GPS that can be used to assist a driver when operating a vehicle. Similarly, planes also use navigation systems and object detection systems that can include a GPS. As detailed above, object detection systems may include the use of an RF detection system. These RF detection systems are able to identify the presence and even the location of an RF transmission source. Notably, this disclosure will specifically focus on the use of an RF transmission detector and source. Accordingly, as used herein, “object detection system” and “RF detection system” may be used interchangeably. Often, these types of RF detection systems include omnidirectional range instrumentation (e.g., antennas), landing instrumentation (e.g., distance measuring devices), Doppler navigation instrumentation, direction finders, etc. Further, RF detection systems utilize antennas to discern objects that are present within a certain environment.
In some circumstances, however, it may be desirable to minimize, or even completely eliminate, detection by an RF detection system. Low Probability of Detection (LPD) systems provide this unique ability. In particular, LPD systems are designed to specifically reduce or eliminate their detectable presence while still transmitting an RF signal. In other words, LPD systems are designed so that foreign (i.e. not a part of the LPD system) RF detection systems are not able to detect the LPD system.
Typical LPD systems employ directional antenna systems that are complicated, expensive, and may limit certain network connectivity. Further, traditional LPD systems that are mounted on vehicles also face detection challenges when those vehicles bank, roll, climb, dive, or otherwise change orientation and/or position. Notably, some traditional LPD systems can also use omni-directional antennas. By way of a brief introduction, omni-direction antennas are much less expensive than directional antennas and allow for a diverse range of potential network topologies. However, because omni-directional antennas allow power to propagate in all directions, traditional LPD systems that use these types of antennas currently face many challenges related to detection and are considered to be quite deficient.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is provided to illustrate only one exemplary technology area where some embodiments described here may be practiced.